The machine is your brain and the ghost is the most primitive part of the human brain consisting of the Thalmus, Hypothalamus, Cerebellum and other lower parts making up the Basal Ganglia. This is sometimes called the “reptilian brain” since it’s from the same parts of the brain we share with all vertebrate animals. Since reptiles were among the first vertebrates it’s sometimes called the “reptilian brain.” Since this part of our brain has changed little over the millions of years of evolution, it’s what Arthur Koestler called the “Ghost in the Machine” in his 1967 book of that title [click the image at left to go the book’s Amazon page].
These very primitive and very small parts of our brain (the hypothalamus is the size of an almond) control a whole lot of our bodily functions, including most of our autonomic nervous system. We die at the moment this reptilian brain shuts down. Think of an electrical panel with a lot of switches called circuit breakers. Any one of them can switch on or off only the part of our house controlled by that switch. Only that part of the house will go dark. But the panel also has a main breaker switch which when flipped to off shuts down all electric current to the entire house.
To continue the metaphor, putting a patient on life support after brain function has ceased is like connecting a portable generator to your house during a power outage. Until and unless the power comes back on you must keep the generator running to have power.
Hunters and others who live in bear country learn that the one and only way to stop a charging bear in its tracks is to put a bullet into the primitive part of its brain. They often describe this tactic as being the same as flipping a switch. Very few riflemen ever achieve this shot and that’s why a charging bear remains a dangerous threat even after absorbing several heavy caliber bullets.
Arthur Koestler believed that this ghost in the machine is responsible not just for many if not most of our vital body functions, but is also heavily involved in our emotional make up and response. It is what he believed led to man’s worst temptation, what he called “Man’s urge to self destruction.”
Our brains consist of two other main parts, the mammalian middle brain and the neocortex. These are later evolved parts of our brain, the neocortex being what makes us modern humans with power of speech, self awareness including the concept of our own impending death, abstract thought, the future in time, etc.
Koestler believed that leaving us with essentially three very different brains instead of evolving one entirely modern brain was a mistake of evolution. It often leads us into behavior that is not in our best interest. It’s the impetus of our urge to self destruction. We go from one hysterical delusion to another, for tulip mania to man-caused climate change to the ridiculous idea that one can change their sex. All this completely discredits the theory of intelligent design by an omnipotent and benevolent creator. There may very well be such a creator, but he, she or it is neither omnipotent nor always benevolent. Who or what would have made us like this, with such a predicament?